A new single-stage isolated power factor preregulator for avionics distributed power supply systems

The flyback topology presents several advantages over the popular boost configuration for the design of power factor preregulators. In particular, the transformer provides input-output isolation and the output may be a low-voltage DC bus as needed in distributed power supply systems. In this paper, the authors show that a flyback power converter operating at the boundary of the discontinuous conduction mode and continuous conduction mode can provide automatic line current shaping. Experimental results taken from a 100 W prototype validate the theoretical analysis